My experience has been that OSX just handles audio a lot better than Windows. I used to use a Dell laptop for Ableton DJing and got frequent drop outs in the sound – CPU and RAM usage was low and I just couldn’t get to the bottom of it. Windows seems more likely to drop out the audio.
When I eventually upgraded to a Mac I didn’t have any trouble at all. One time Traktor’s screen locked up but the music carried on playing regardless and eventually the screen came back.